With the GDL 39 you can receive ADS-B weather transmissions when you’re in line of sight with an FAA ground station and display that weather on Garmin’s brand-new Garmin Pilot iPad app (more on that product in a bit). The weather, as we’ve written about before, is very good, though not quite as good as Sirius XM Weather. The big advantage of ADS-B weather is that you not only get most of the weather products you care about at reasonably good quality, but there’s no subscription, as there is for Sirius XM Weather, for instance. The downside is that, because it’s a ground-up system, you can’t always get reception. This is true for ADS-B weather in general, regardless of the receiver or whether it’s permanently installed or mounted or a portable unit. The weather you get with the GDL 39 is good, and the display of weather on Garmin Pilot on your iPad is excellent, with the weather information, animated Nexrad, graphical metars, winds and more shown on the main map page and also integrated into various airport information pages so you can check the weather without changing screens. The integration of ADS-B weather into Garmin Pilot is top-drawer.